1. Field of the Invention
The present invention relates to a peripheral device to be connected with a host device, and a method of connecting a peripheral device with a host device.
2. Description of the Related Art
A peripheral device, such as an external storage device, is connected with a host device, such as a personal computer via one of various available interfaces to perform data communication. USB interfaces are known as of such available interfaces. Among the USB interfaces, USB 3.0-compliant interfaces (hereafter referred to as ‘USB 3.0 interfaces’) have recently spread widely, in addition to USB 2.0-compliant interfaces (hereafter referred to as ‘USB 2.0 interfaces’).
The USB 2.0 and USB 3.0 standards have different data communication-related specifications, such as, for example, a communication mode (half-duplex system or full-duplex system) and the number of signal lines. The USB 2.0 interface has a data transmission rate of 480 Mbps at the maximum, while the USB 3.0 interface has a data transmission rate of 5 Gbps at the maximum. The USB 3.0 interface accordingly enables higher-speed data communication, compared with the USB 2.0 interface. The USB 3.0 interface has downward compatibility in physical use of a port. Both a USB male connector compliant with USB 2.0 (hereafter referred to as ‘USB 2.0 connector’) and a USB male connector compliant with USB 3.0 (hereafter referred to as ‘USB 3.0 connector’) are connectable to a USB port compliant with USB 3.0 (hereafter referred to as ‘USB 3.0 port).